Inter-dependence simply means that you only exist in a context, you cannot exist without a context, independently. You 'appear' in the midst of other phenomena.

Vis-à-vis other beings, inter-dependence basically insists that the context you arise "out of" is by definition "not you", thus the context includes all 'others'.

Without context, you don't exist: without others, you don't exist.
'They' participated in shaping the bundle of thoughts that presently identify themselves as a 'unified' group called 'you'. In good or bad!

Inter-dependence is about how the context shapes you. One way to think of it is: the world (including 'others') is the 'mould' from which you are created! The mould can be 'perfect' or 'defective' (that's a mental fabrication, a story), but this mould makes "who you are".
It can do so by providing stuff, things, opportunities, or it can do so by not providing them and forcing you to acquire other things or the same things but by another route… Basically, the context is what makes you learn thanks to a teacher and lessons, or thanks to trial and errors, or not learn at all because you wouldn't have even access to the hints that something might exist or be possible!

The context makes who you are, this is selflessness.

You merely selectively pick some elements of reality and appropriate them as 'yours': "this is who I am" as if this was definable out of context!

To create this illusion of separation between you and the context, you might create a split (at least in narrative) e.g. between the past and the present…

For example, you'll accept that you are dependent on the context of learning a particular skill, but "now you know", you supposedly don't depend on the context anymore…

This is tempting, but this is a delusion: what would "I know how to do this-or-that" mean if suddenly you were thrown in a community where there's no use for such a skill and no one ever heard of it being possible, e.g. computer science in an aboriginal society? No one would understand what you mean when you'd say 'computer'… Or another, even less appealing example, what would "I know how to type" mean if you suddenly lost your fingers in an accident?

This 'I' in "I know" is a delusion, which exists only in a particular context!

This is inter-dependence, and this has nothing to do with what people would commonly understand about "depending on others" (a narrative of weakness, rather than a narrative of contextual-ness).